Printer/Print Station is Offline
- Printer Offline
- Adjusting the Sleep settings on your host PC
- macOS: Troubleshooting the Print Client
- Uninstalling the Support Tool
- Troubleshooting USB Connection
Printer Offline
If you're unable to print, follow these steps to troubleshoot. After each step, check to see if you can print; if you still can't, then move on to the next step.
Before you start, take the time to identify your printer model so you know which instructions apply to you.
Step 1: Make sure the printer isn't paused.
Printers will not print if they're paused. Depending on the model of your printer, you'll see different indicators if the printer is paused.
T800: "OFFLINE" in top-right corner
The OFFLINE text means the printer is paused. Unpause it using the green pause button [ I I ] below the screen.
ZD621R: Pause indicator above screen
If the PAUSE light is lit up yellow, the printer is paused. Unpause it using the Pause button [ I I ] to the right of the screen.
ZD500R: PRINTER PAUSED message flashing on screen
If the printer's screen flashes PRINTER PAUSED, unpause it using the Pause button [ I I ] to the right of the screen.
Step 2: Refresh the Print Client.
Using the Support Tool, select the Refresh Print Client option.
If you haven't installed the Support Tool, follow these instructions:
Windows: https://kb.simplerfid.com/books/support-tool/page/installation
Mac: https://kb.simplerfid.com/books/support-tool/page/support-tool-installation-mac
If you find that you have to Refresh the Print Client often, it may help to adjust the sleep settings on your host PC.
Mac:
https://kb.simplerfid.com/books/support-tool/page/refresh-print-client-mac
Step 3: If using USB, check the printer's USB connection.
Occasionally, the Host PC will put certain USB ports to sleep in order to save power.
Unplug the USB cable from both ends then plug it back in.
Please make sure that no USB hubs are used.
If you suspect or find your cable damaged, you can take the cable (USB A>B) from a regular inkjet/laser printer.
Step 4: Power cycle the printer.
Printers can encounter software errors which cause them to stop responding to the host.
Turn the printer off for 30 seconds, then turn it back on.
- T800: Turn the printer off using the power switch on the back.
- ZD621R: Turn the printer off by holding down the Power button to the left of the screen.
- ZD500R: Turn the printer off using the power switch on the back.
Step 5: Repair the Print Client.
Repairing the print client will download and run the installer in order to write over any parts of it that may have been damaged. This is particularly useful if the Refresh Print Client option throws an error.
Please make sure you are using the latest version of the Support Tool; previous versions will reset your station pairing, meaning you will need to contact support to re-attach your station if you use the Repair function on those older versions.
Mac:
https://kb.simplerfid.com/books/support-tool/page/repair-print-client-mac
Wait a few minutes after the repair process completes for your station to come online. If you continue to face issues, please contact support.
Adjusting the Sleep settings on your host PC
If your host PC keeps disconnecting from the Simple RFID website it's likely that your host PC is going to sleep. Here's how to prevent it.
Windows 11
- From the Windows start menu, search "Sleep" and click the following result:

- In the Settings window that appears, set "When plugged in, put my device to sleep after" to "Never":

Windows 10
- From the Windows start menu search "Sleep"
- Then in the Settings section set the Sleep options to "Never"

macOS: Troubleshooting the Print Client
UPDATE: The macOS version of the Support Tool has been released, which provides quick access to Refresh and Repair functions. In most cases you should use the Support Tool rather than the commands below.
Introduction
The macOS Print Client is currently in beta. As such, it has a couple of known issues:
- The print client will not run if certain USB storage devices are plugged into the Mac
- The print client does not support Printronix printers via USB; use a network connection
Troubleshooting
The following commands can be copy/pasted into Terminal to take action on the print client.
These commands require Administrator access to the Mac. When using sudo, you'll periodically be prompted for your password in order to escalate your privileges. These commands can also be used in a root shell by omitting sudo.
As always, please exercise caution when using the terminal, especially with elevated privileges. Make sure you fully understand any command you're using, otherwise you may damage your system.
Get ClientId from PrintClientDatabase
The ClientId is the station's unique identifier when communicating with our servers. This value can be useful for identifying a station when troubleshooting.
sudo sqlite3 /var/root/Library/Application\ Support/Simple\ RFID/PrintClient/PrintClientDatabase.db "SELECT ClientId from RegistrationData"Refresh Print Client
sudo launchctl kickstart -k system/com.simplerfid.printclientThe print client (and its updater) are handled as services by launchd in macOS. The above command instructs launchd to refresh the print client by "kickstarting" the process, with -k indicating that the process should be killed if it is already running.
If you receive the error Could not find service "com.simplerfid.printclient" in domain for system, the print client is not installed, or has been manually disabled. Install or re-enable the print client to continue.
Disable Print Client
sudo launchctl bootout system/com.simplerfid.printclient
sudo launchctl bootout system/com.simplerfid.printclient.update
sudo launchctl bootout system/com.simplerfid.printclient.updater.selfupdateThese three commands stop the print client and its updater processes, and unload the services from the system domain. This will prevent the print client from starting or updating automatically.
While not recommended, these commands can also be used independently of each other to control specific components.
Re-enable Print Client
sudo launchctl bootstrap system /Library/LaunchDaemons/com.simplerfid.printclient.plist
sudo launchctl bootstrap system /Library/LaunchDaemons/com.simplerfid.printclient.update.plist
sudo launchctl bootstrap system /Library/LaunchDaemons/com.simplerfid.printclient.updater.selfupdate.plistThese three commands load the print client and updater services back into the system domain, effectively re-enabling them all. Since these services are not currently in the domain, we provide the full path to each service's plist.
After this is complete, launchd will continue launching these services automatically on their respective intervals.
Run Print Client manually
(cd "$(printf '%s\n' /Applications/SimpleRfid/PrintClient.[0-9]* | sort -V | tail -n1)" && ./SimpleRFID.PrintClient)The parentheses start a subshell where we temporarily cd into the target directory, run the command, and then automatically return to the original directory when the subshell exits.
The print client should function exactly the same as if it was started by launchd, except you may be able to see some output from the application, for troubleshooting purposes. If you close the terminal window or press Ctrl-C, the process will terminate.
Uninstall Print Client
: # Unload the services from the system domain
sudo launchctl bootout system/com.simplerfid.printclient
sudo launchctl bootout system/com.simplerfid.printclient.update
sudo launchctl bootout system/com.simplerfid.printclient.updater.selfupdate
: # Delete the plist files defining the services
sudo rm -f /Library/LaunchDaemons/com.simplerfid.printclient.plist
sudo rm -f /Library/LaunchDaemons/com.simplerfid.printclient.update.plist
sudo rm -f /Library/LaunchDaemons/com.simplerfid.printclient.updater.selfupdate.plist
: # Delete the SimpleRfid folder in /Applications containing the print client and updater
sudo rm -rf /Applications/SimpleRfid
: # Delete temporary files
sudo rm -rf "/tmp/Simple RFID"
: # Delete the receipts for previous installs
pkgutil --pkgs | grep com.simplerfid.printclient.updater | xargs -n1 sudo pkgutil --forget
: # OPTIONAL: Delete the Application Support data for the print client
: ## This will require you to contact support to re-attach the station to your
: ## account if you reinstall the print client in the future.
sudo rm -rf "/var/root/Library/Application Support/Simple RFID"These commands should remove any trace of the print client from your system. You can always install the print client again using the installer from the Resources page on the web portal.
Download and install Print Client via command line
: # Download the latest installer from GitHub
curl -L0 -o /tmp/PrintClient.Updater.arm64.pkg https://github.com/simplerfid/printclient-updater/releases/latest/download/PrintClient.Updater.arm64.pkg
: # Run the installer
sudo installer -pkg /tmp/PrintClient.Updater.arm64.pkg -target /These commands download the latest installer and run it from the command line with no GUI.
Depending on your internet speed, your terminal may sit for a while at installer: Installing at base path / while the updater downloads the latest print client files. When the process is complete, you should see installer: The install was successful.
Uninstalling the Support Tool
It may be necessary to reinstall the Support Tool to ensure you have the latest version on your computer.
To do this, log in to the computer that has the Support Tool installed. Then go to Settings > Apps > Installed apps
In the search bar that says "Search apps", type in "Simple RFID Support Tool".
Older versions of the Support Tool were named "Print Client Refresh Tool". If "Simple RFID Support Tool" does not pop up, then try this name. If neither of the names shows anything, then go straight to downloading the Support Tool here: https://kb.simplerfid.com/books/support-tool/page/support-tool-installation-windows
Click on the 3 dots on the right, and select "Uninstall". Now install the support tool and refresh the Print Client.
Please note that this will create a new Printer Station, so you will need to contact support here: https://support.simplerfid.com/support/tickets/new
Troubleshooting USB Connection
In the Windows Search bar, type Device Manager and open it.
Expand the Universal Serial Bus controllers section in the Device Manager window.
Right-click the device with the warning icon, which is USB Root Hub (USB 3.0), and click Disable device.
Wait a couple of seconds for the same device to appear with the "down arrow" icon, then right-click it and select Enable Device.
a couple of seconds for the same device to appear with the "down arrow" icon, then right-click
Now, the USB Root Hub (USB 3.0) should appear with the regular icon and work properly.